The SU-122 (from ''
Samokhodnaya Ustanovka 122 mm'') was a
Soviet
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...
self-propelled howitzer
Self-propelled artillery (also called locomotive artillery) is artillery equipped with its own propulsion system to move toward its firing position. Within the terminology are the self-propelled gun, self-propelled howitzer, self-propelled mo ...
or
assault gun
Assault gun (from german: Sturmgeschütz - "storm gun", as in "storming/assaulting") is a type of self-propelled artillery which uses an infantry support gun mounted on a motorized chassis, normally an armored fighting vehicle, which are designed ...
used during
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
. The number "122" in the designation represents the caliber of the main armament, a
122 mm M-30S howitzer. The chassis was that of the
T-34
The T-34 is a Soviet medium tank introduced in 1940. When introduced its 76.2 mm (3 in) tank gun was less powerful than its contemporaries while its 60-degree sloped armour provided good protection against Anti-tank warfare, anti-tan ...
.
Development history
The Soviet High Command became interested in assault guns following the success of German
Sturmgeschütz III
The ''Sturmgeschütz III'' (StuG III) assault gun was Germany's most-produced fully tracked armoured fighting vehicle during World War II, and second-most produced German armored combat vehicle of any type after the Sd.Kfz. 251 half-track. I ...
s. Assault guns had some advantages over
tanks with turrets. The lack of a turret made them cheaper to produce. They could be built with a larger fighting compartment and could be fitted with bigger and more powerful weapons on a given chassis. However, assault guns generally aim by orienting the entire vehicle, and were thus less suited for close combat than tanks with turrets.
In April 1942, design bureaus were asked to develop several assault guns with various armament:
76.2 mm ZiS-3 divisional field guns and 122 mm M-30 howitzers for infantry support, and 152 mm ML-20 howitzers for attacking enemy strongholds.
A prototype assault gun, armed with the 122 mm howitzer and built on the German Sturmgeschütz III chassis was developed, designated ''SG-122''. Only 10 of these were completed. Production was halted when the vehicle was found to be hard to maintain and judged to be unsuccessful.
Simultaneously, an SPG based on the T-34 medium tank was also developed. Initially, the T-34's chassis was selected for the 76.2 mm F-34 gun. This vehicle, the ''U-34'', was created in the summer of 1942 at UZTM (Uralmashzavod – Uralsky Machine Building factory) design bureau, by N. W. Kurin and G. F. Ksjunin. It was a tank destroyer with the same armament as the T-34, but without a turret. The vehicle was 70 cm lower than a T-34, had thicker armor, and was 2 tonnes lighter. It did not enter production.
UZTM then worked on combining features of the ''U-34'' and the ''SG-122''. Initial design work was completed between July and August 1942. The project emphasized minimizing modifications to the platform and the howitzer. It used the same chassis, superstructure, engine and transmission as the ''U-34'' and was armed with (the then new) 122 mm M-30S howitzer from F. F. Petrov's design bureau. This vehicle also used the same gun bed cover and mountings as the SG-122, to keep costs low and simplify production. It had 45 mm thick frontal armor. The M-30S howitzer could be elevated or depressed between −3° and +26° and had 10° of traverse. The five-man crew consisted of a driver, gunner, commander and two loaders.
By 25 November 1942, the first ''U-35'' prototype was ready. Trials ran from 30 November to 19 December 1942, and uncovered various faults in the design, including insufficient elevation, a flawed shell transfer mechanism, poor ventilation for the crew compartment, and the fact that the commander had to assist in operating the gun, which made him unable to successfully carry out his other duties. The ''U-35'' entered service with the Red Army as the SU-35 (later renamed SU-122) despite these faults.
Production SU-122s were based on an improved prototype built after trials were conducted. They incorporated several modifications, including slightly less sloped front armor to ease production, modified layout of the fighting compartment (the location of crew member stations and ammunition racks were changed), fewer vision slots, and a periscope for the commander. The first production vehicles were completed before 1943.
Production history
SU-122 production began in December 1942 with 27 vehicles built that month. The original plan for production beyond that point was to produce 100 SU-122s each month. Production continued until the summer of 1943, by which time a total of 638 SU-122s had been built.
Service history
The first SU-122s produced in December 1942 were sent to training centers and two new combat units, the 1433rd and 1434th self-propelled artillery regiments. Initially, each of these mixed regiments consisted of two batteries with four SU-122s each and four batteries with four
SU-76
The SU-76 ('' Samokhodnaya Ustanovka 76'') was a Soviet light self-propelled gun used during and after World War II. The SU-76 was based on a lengthened version of the T-70 light tank chassis and armed with the 76 mm divisional gun M1942 (ZiS-3) ...
tank destroyers each. Each regiment had an added SU-76 tank destroyer as a command vehicle. It was planned to raise 30 self-propelled artillery regiments operating within armoured and mechanized corps.
In January 1943, the 1433rd and 1434th self-propelled artillery regiments were sent to the Volkhov Front near
Leningrad
Saint Petersburg ( rus, links=no, Санкт-Петербург, a=Ru-Sankt Peterburg Leningrad Petrograd Piter.ogg, r=Sankt-Peterburg, p=ˈsankt pʲɪtʲɪrˈburk), formerly known as Petrograd (1914–1924) and later Leningrad (1924–1991), i ...
as part of the 54th Army. On 14 January, they saw combat for the first time in Smierdny region. After that, it was decided SU-122s should follow between 400 m and 600 m behind the attacking tanks; sometimes this distance was shortened to between 200 m and 300 m.
The use of SU-76 tank destroyers together with SU-122s proved unsuccessful. Based on combat experience, the organization of self-propelled artillery regiments was changed; the new regimental organization consisted of two batteries of SU-76 tank destroyers and three batteries of SU-122s, for a total of 20 self-propelled guns. In April, the organization of self-propelled artillery regiments was again changed. Separate regiments were created for SU-76 tank destroyers (light self-propelled artillery regiment) and SU-122s (medium self-propelled artillery regiment).
The medium self-propelled artillery regiment consisted of four batteries of four SU-122s each. Each regiment was also equipped with either an added SU-122 or a T-34 for the commander and a
BA-64
The BA-64 (''БА-64'', from ''Bronirovaniy Avtomobil'', literally "armoured car") was a Soviet four-wheeled armoured scout car. Built on the chassis of a GAZ-64 or GAZ-67 jeep, it incorporated a hull loosely modeled after that of the Sd.Kfz. ...
armoured car. This organization remained in place until the start of 1944 when the SU-122 began to be replaced by the
SU-152
The SU-152 (russian: самоходная установка-152, СУ-152, Samokhodnaya Ustanovka-152) is a Soviet self-propelled heavy howitzer used during World War II.
It mounted a 152 mm gun-howitzer on the chassis of a KV-1S heavy tan ...
,
ISU-122
The ISU-122 (acronym of'' Istrebitelnaja - or Iosif Stalin-based - Samokhodnaya Ustanovka 122'') was a Soviet assault gun used during World War II, mostly in the anti-tank role.
History and purpose
A prototype of the ISU-122 (in Russian ИСУ- ...
and
ISU-152
The ISU-152 (russian: Самоходная установка на базе танка ИС с орудием калибра 152мм, ИСУ-152, Samokhodnaya Ustanovka na baze tanka IS s orudiyem kalibra 152mm, meaning " IS tank based self-prope ...
heavy self-propelled guns, and the
SU-85
The SU-85 ('' Samokhodnaya ustanovka'' 85) was a Soviet self-propelled gun used during World War II, based on the chassis of the T-34 medium tank. Earlier Soviet self-propelled guns were meant to serve as either assault guns, such as the SU-122, ...
tank destroyers.
The SU-122 proved effective in its intended role of direct fire on strongholds. The massive concussion of the 122 mm high explosive round was reportedly enough to blow the turret off even a
Tiger I
The Tiger I () was a German heavy tank of World War II that operated beginning in 1942 in Africa and in the Soviet Union, usually in independent heavy tank battalions. It gave the German Army its first armoured fighting vehicle that mounted ...
if a direct hit was scored, a trait shared with the larger 152 mm howitzers. A new BP-460A
high-explosive anti-tank
High-explosive anti-tank (HEAT) is the effect of a shaped charge explosive that uses the Munroe effect to penetrate heavy armor. The warhead functions by having an explosive charge collapse a metal liner inside the warhead into a high-velocity ...
(HEAT) projectile was introduced in May 1943; however, its primitive warhead design was only minimally more effective than brute concussive effects of the older high explosive shell. However, like most howitzers, the accuracy of the M-30 was less than that of contemporary weapons designed for
anti-tank warfare
Anti-tank warfare originated from the need to develop technology and tactics to destroy tanks during World War I. Since the Triple Entente deployed the first tanks in 1916, the German Empire developed the first anti-tank weapons. The first devel ...
.
[http://www.panzer-war.com/page34.html Russian Tank Gun Accuracy]
At least one SU-122 was captured by the German Army.
Few SU-122s survived the war. Currently only one exists and is on display in the
Kubinka Tank Museum
The Kubinka Tank Museum (Центральный музей бронетанкового вооружения и техники - Tsentral'nyy Muzey Bronetankovogo Vooruzheniya I Tekhniki -Central Museum of Armored Arms and Technology) is a larg ...
.
Variants
The SU-122 had no variants that went into mass production. The T-34 chassis of the SU-122 was further adapted as part of the later
SU-85
The SU-85 ('' Samokhodnaya ustanovka'' 85) was a Soviet self-propelled gun used during World War II, based on the chassis of the T-34 medium tank. Earlier Soviet self-propelled guns were meant to serve as either assault guns, such as the SU-122, ...
self-propelled gun.
SU-122M
Even as the SU-122 was being mass-produced, its design was being refined primarily with an eye to reduce production costs. The M-30S armament proved poorly suited for purpose, in spite of its prior recommendation by the GAU RKKA artillery committee. The howitzer took a lot of space and required both commander and gunner to operate it in order to fire. Because of this, in January 1943, work began on fitting the SU-122 with a different howitzer.
The prototype SU-122M was built in April 1943. It featured a bigger fighting compartment as well as an individual driver's hatch. The M-30S howitzer, mounted on the floor of the vehicle, was replaced by the more modern D-11 howitzer (a variant of U-11 howitzer). However, the SU-122M was not put into production due to a decision to proceed with the
SU-85
The SU-85 ('' Samokhodnaya ustanovka'' 85) was a Soviet self-propelled gun used during World War II, based on the chassis of the T-34 medium tank. Earlier Soviet self-propelled guns were meant to serve as either assault guns, such as the SU-122, ...
instead.
SU-122-III
Another attempt to create an improved SU-122 replacement took an
SU-85
The SU-85 ('' Samokhodnaya ustanovka'' 85) was a Soviet self-propelled gun used during World War II, based on the chassis of the T-34 medium tank. Earlier Soviet self-propelled guns were meant to serve as either assault guns, such as the SU-122, ...
chassis and paired it with the 122-mm D-6 howitzer, which was lighter and smaller than the U-11 howitzer. This was unsuccessful, due to the unreliability of the howitzer's recoil mechanism and its poor anti-tank abilities. Subsequent wartime design work on 122 mm self-propelled howitzers was cancelled.
References
*
External links
Battlefield.ru
See also
*
List of Soviet tanks
Below is a list of tanks and other armoured fighting vehicles of the Russian empire, Soviet Union, the Russian Federation, and Ukraine.
Imperial Russia, World War I
Armored tractors
*Gulkevich's armored tractor
*F. Blinov armored tractor
*Wa ...
– covers all periods
{{WWIISovietAFVs
World War II tank destroyers
World War II assault guns
Assault guns of the Soviet Union
122 mm artillery
Uralmash products
Military vehicles introduced from 1940 to 1944